Multi-Kepler GPU vs. multi-Intel MIC for spin systems simulations

We present and compare the performances of two many-core architectures: the Nvidia Kepler and the Intel MIC both in a single system and in cluster configuration for the simulation of spin systems. As a benchmark we consider the time required to update a single spin of the 3D Heisenberg spin glass model by using the Over-relaxation algorithm. We present data also for a traditional high-end multi-core architecture: the Intel Sandy Bridge.

IMPROVED APPROXIMATION OF MAXIMUM VERTEX COVERAGE PROBLEM ON BIPARTITE GRAPHS

Given a simple undirected graph G and a positive integer s, the maximum vertex coverage problem (MVC) is the problem of finding a set U of s vertices of G such that the number of edges having at least one endpoint in U is as large as possible. The problem is NP-hard even in bipartite graphs, as shown in two recent papers [N. Apollonio and B. Simeone, Discrete Appl. Math., 165 (2014), pp. 37-48; G. Joret and A. Vetta, Reducing the Rank of a Matroid, preprint, arXiv: 1211.4853v1 [cs.DS], 2012].

GAUSS-DIFFUSION PROCESSES FOR MODELING THE DYNAMICS OF A COUPLE OF INTERACTING NEURONS

With the aim to describe the interaction between a couple of neurons a stochastic model is proposed and formalized. In such a model, maintaining statements of the Leaky Integrate-and-Fire framework, we include a random component in the synaptic current, whose role is to modify the equilibrium point of the membrane potential of one of the two neurons and when a spike of the other one occurs it is turned on. The initial and after spike reset positions do not allow to identify the inter-spike intervals with the corresponding first passage times.